A simple explanation and corrected version of a sentence about a daddy penguin keeping an egg warm, suitable for an 8-year-old student.
Let's look at the sentence you wrote:
"A daddy penguin holds the egg on its feet to keeps it warm so a mum can go to eat."
There is a small grammar mistake. When you use "to" followed by a verb, the verb should be in its base form without s. So, "to keeps" should be changed to "to keep."
Also, we can improve it a little by saying "a mum penguin" instead of just "a mum" so it's clear that we are talking about the penguin mom. Here's a corrected version:
"A daddy penguin holds the egg on its feet to keep it warm so the mum penguin can go to eat."
This sentence means the daddy penguin keeps the egg warm while the mom penguin goes to find food.